This invention was made under a contract with the Department of the Air Force.
This invention is related to lasers and more particularly to an improved laser optical resonator assembly.
Certain gas lasers are constructed with a sealed housing or casing in which the gas and electrodes are contained and with resonator mirrors mounted externally of the casing. The advantages of an external resonator are simplified optical adjustments and permanently sealed window assemblies which maintain vacuum or pressure integrity of the interior of the housing. A disadvantage is additional intracavity loss introduced by the windows. One type of external resonator assembly for a gas transport laser of this type is described in a book entitled, "Lasers" by B. A. Lengyel (John Wiley & Sons, New York, 1962), and comprises mirror support plates at the front and rear ends of the laser mounted on an optical bench and extending the full length of the laser. While this external resonator assembly is generally effective, it has the disadvantages of being heavy, unstable, and somewhat bulky.
This invention is directed to an improved resonator assembly which avoids these disadvantages.